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Apache Guacamole, MC, SQLite3, Peewee, OpenBazaar, IPv6, SSD, ext4

posted Jun 25, 2016, 9:28 PM by Sami Lehtinen   [ updated Jun 25, 2016, 9:28 PM ]
  • Sigh, why does Midnight Commander (mc) require libssh2-1 and unzip, I love mc. But I don't what I would do actually with those two outdated libs.
  • Quickly played with Apache Guacamole. It's great, I've been actually looking for something like that. Maybe I'll give it a real spin soon. Something more than just 15 minutes in a VM.
  • Decided to finally kill in favor of other hobby projects. There's only limited amount of time to get things done.
  • When I said that I'll close down LclBd because lack of suitable server, a friend of mine said he'll provide a free server. So it took only 10 minutes to setup the site back up'n'running. Yet, I've blocked new user registrations. Service will be shutdown when domain expiration should be done next time.
  • Database Locked with SQLite3? Just sleep a while and retry write. Unless you're having some locking issues or something silly like long running write transactions open. Yes, that's a guaranteed fail. Even more methods to Fingerprint Web Browser users, newest technology is called Acoustic Fingerprint, here's a working demo called Audio Fingerprint. Yet technically using return of some generated signal for fingerprinting isn't anything new, of course. It's decades old technology.Todays advanced signal processing capabilities make it just much more powerful.
  • After upgrading to latest version of Peewee I've been getting InterfaceError messages about parameter binding, which I haven't ever seen before. Maybe I'm doing something wrong, maybe not? Also those exceptions seem to easily leave cursor open and prevent prover WAL file processing with SQLite3 . Any pro tips, anyone? "peewee.InterfaceError: Error binding parameter 0 - probably unsupported type." Haven't yet had time to properly debug that, just wondering at this moment. But I'll figure it out soon enough hopefully.
  • Blog post: OpenBazaar Needs Freenet. Well, I've liked Freenet too. But signed key value storage isn't good for everything. If everything is built on top of it, it might end up being a really terrible technical kludge. Even if that might work locally, on distributed network it's lot slower. I'm also bit skeptical about IPFS, but to be honest. I haven't tried it. It's marketing hype was just so full of vapor that it did really badly annoy me. Keywords: Anonymity, Bitcoin, Darknet, Freenet, Liberty, markets, OpenBazaar, Privacy.
  • Configured Apache Guacamole for testing environment using Ubuntu, Docker, PostgreSQL (Postgres), guacd and guacamole itself. Guacamole provides clientless remote desktop access. There's just one really strange thing, don't really get what takes so long when starting the guacamole container. Tomcat starts and fails.... But after a long delay, something like 15 minutes, it starts to work. I've checked that the database is guaranteed to be available and correctly configured. I hope this gets fixed in coming releases. If required, I can provide additional information.
  • Large IPv6 UDP packets [pdf]. Packet fragmentation is a big problem. Been there done that, with some apps I sent large UDP packets and some fragments were always missing, it it worked well for LAN.
  • Configured all systems to use units in gigabytes to reduce confusion and improve readability.
  • Do SSD drives lose data when stored extensively unpowered? Some say yes, some say no. - I guess it's not that simple. It's just like they said that CDs retain data foor 100+ years, but truth is that I've thrown out all of my RW disks except a few ones, because those have anyway lost the data. Or it has become unreadable, which is actually the same thing. So is the data retention 3 years or 200 years? Probably somewhere between depending on multiple factors. - I love when people give simple answers to complex questions. Because these are questions where there is no simple answer. Only time will tell. For real results you should do long term large scale extensive testing with scientific data collection.- That's the only way to get results, and even if that is done. Someone will argue about the placement of drives and what kind of background radiation those were exposed to and so on. - Only time will tell. Meanwhile, keep multipel copies and refresh those and check data integrity.
  • It's like the discussion where people claimed that ext2 is better for flash drives than ext4, because it doesn't do journaling. Well well. Who says you couldn't use ext4 without journal too? It's so easy about being wrong about almost anything. Many programs and platforms can be configured in millions of ways, there are multiple vendors, there are different environments and to sum it up, stuff like ext4 is open source, so you can change the source, recompile it and use it with your own parameters. Dropping something like journaling shouldn't be too big job, because it's likely to be very concentrated in code & libs. Breaking it on purpose isn't hard task, even if there wouldn't be pre-existing parameter for it.
  • Found out why Guacamole / Tomcat start was so ridiculously slow. Here's the reason: 26-May-2016 08:44:05.084 INFO [localhost-startStop-1] org.apache.catalina.util.SessionIdGeneratorBase.createSecureRandom Creation of SecureRandom instance for session ID generation using [SHA1PRNG] took [1,329,626] milliseconds. Actually that's not a big problem, server is restarted very rarely. But it's still very annoying if users happen to wait for that to happen. Classic engineering. All users thought that that doesn't make any sense whatsoever.